Taylor Swift and her American football-player fiancé Travis Kelce have kicked off rumoured wedding celebrations at Madison Square Garden in New York City.

High-profile friends of the couple, from actress Lena Dunham to frequent collaborator Jack Antonoff were spotted Thursday evening in formal attire.

Aerial footage showed a stream of black SUVs pulling up to the venue with guests dropped off under a white canopy tent. Media speculation has dubbed the event both a pre-party and possible rehearsal dinner.

Around 100 people were expected at the event on Thursday, ahead of a much larger celebration on Friday boasting up to 1,000 guests at the arena.

Throughout the day on Thursday, a small army of cops sweated it out in asphalt-curdling heat while camera crews tried to catch a glimpse of anything that would confirm what was happening inside the arena, which is home to multiple sports teams in the city.

Celebrity gossip outlet TMZ fired up a live feed of what appeared to be one of the Garden’s loading bays, where for several hours one could watch stationary forklifts and the occasional event staffer sneaking a cigarette.

Viewers who tuned in at approximately 18:00 ET (22:00 GMT) could see, in real time, as several men in cargo shorts hauled cardboard boxes from the back of a van.

Reporters chronicled every metal barricade plunked down by police and each time people were told to move back from areas near the arena, to make way for the event and guests.

Cameras spotted a large sign near an entrance that warned those going inside the venue from 29 June – 3 July would be consenting to video and photos being taken inside the arena for an “event”, suggesting there was perhaps filming happening inside during the preparations.

On Thursday evening, the couple donated $26m (£19.4m) to charities in the US close to their hearts, including organisations in New York, Nashville, where Swift started her music career and Kansas City, the home of Kelce’s NFL team.

Swift’s representatives, while not mentioning anything about a wedding, told BBC News the donation which included food banks, was for “charities across the United States”.

A permit for the events on Thursday and Friday obtained by the Associated Press said about 100 guests would start arriving around 17:30 ET for a “pre-party night”, which would go until 22:30 ET.

Guests at the wedding will reportedly not be allowed to have their phones during the main ceremony, which is expected to begin with mid-afternoon cocktails before a reception going into the night.

As crews were setting up on Thursday, the BBC confirmed a large white canopy tent sitting outside the venue was to be used for guest arrivals, though VIPs like Swift and Kelce still planned to use underground entry to the arena for added privacy.

Fans gathered outside, even after their mayor explicitly and repeatedly told them to please stay inside on a day when temperatures topped 100F (37C).

“I’m here to see the alleged wedding,” said Swift fan Ryan Weng, “because I’ve been loving her for more than 15 years, so it’s going to be a very, very amazing and irreplaceable experience for me and my entire life.”

Fellow fan Rusty Carbaug, a pilot in her 30s who dropped by the Garden to wish Swift well, donned a Kansas-themed T-shirt in honour of Kelce, who plays for the Kansas City Chiefs.

“I feel like I grew in my music taste with her,” said Carbaug, adding: “The right man for her is whoever she chooses.”

For several days, media outlets have watched every move outside the arena. They spotted trucks with cryptic labels like “GP” and “garden party” on it and crews unloading tons of equipment and things like large white staircase prop and large mirror ball. Earlier in the week, workers were seen rolling out a red carpet, which was hastily withdrawn.

New York City Mayor Zohran Mamdani, an astute student of both politics and pop culture, has coyly alluded to the wedding chatter during press conferences.

City officials confirmed to the BBC that somebody applied for street closure permits in the area, but did not reveal whom.

But the city is not likely to have shut down Manhattan’s busiest corridor on a holiday weekend for just anybody. And this is not just any holiday weekend, it’s 4 July weekend marking America’s 250th birthday while the city also hosts the World Cup.

The speculation heightened.

Then the celebrities started to emerge.

Paparazzi captured images of Antonoff, Swift’s longtime producer, sporting a tux and a toothpick dangling out of his mouth, reportedly heading to Thursday’s event at the Garden.

His sister Rachel Antonoff, a designer, followed closely behind in a bubblegum-pink dress.

Famed American sports broadcaster Erin Andrews was also seen in a silver sparkly gown and Swift’s longtime publicist, Tree Paine, wore a light blue dress.

US tabloid Page Six reported Bradley Cooper and Gigi Hadid, a longtime member of Swift’s friend circle, had also arrived at the venue.

Pop star and actress Selena Gomez posted images of herself on Instagram wearing a black gown with gem earrings and heading to an unspecified event.

People Magazine published a video of Dunham, who created the series Girls, being chauffeured through Manhattan in a black SUV.

Swift reportedly left Thursday night’s event, external at Madison Square Garden well after midnight, arriving home in the early hours of Friday morning.

Though Madison Square Garden is a core piece of New York iconography, it is not exactly aesthetically pleasing. It is an imposing black puck of a building squatted over the most claustrophobic transit hub in America.

For many who know New York and the sports arena, it was difficult to imagine an artist so careful with imagery tying the knot inside, where no amount of floral arrangements could disguise the fact that it is a six-decade-old sports venue whose floors are laminated with generations of sweat and beer.

University of Mississippi students Elizabeth Maxey, 21 and Hayden Mason, 19, initially did not believe their favourite singer would actually choose the Garden.

But when they heard about the street closures, they realised, “OK, this is gonna be something real. It’s gonna be happening”, Mason said.

With Swift’s resources, “You’re gonna be able to make anything look pretty,” Maxey chimed in.

Even if the venue was unexpected, Swift’s loyal fans were prepared to celebrate regardless.

Laura Bonne, a 20 year old tourist visiting from Belgium who was waiting outside the Garden, praised Swift’s decision on the venue. “I think its nice because she’ll have a lot of privacy.”

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